Problem: Rewrite ${((8^{-7})(9^{3}))^{-9}}$ in the form ${8^n \times 9^m}$.
Solution: ${ ((8^{-7})(9^{3}))^{-9} = (8^{(-7)(-9)})(9^{(3)(-9)})} $ ${\hphantom{ ((8^{-7})(9^{3}))^{-9}} = 8^{63} \times 9^{-27}} $